CueKit 🚂

Interruptible queuing system for closures

on cue - a signal for action

Description 🏷

A way to run tasks one after the other. (with support for canceling tasks)

Problem 🤯

• Hard to queue up tasks that needs to be preformed one after the other
• Hard to unit-test network code
• Async network code all over the place is hard to reason about and hard to make bug free
• Features such as timeout and retry are hard to build into DispatchWorkItem or NSOperationQueue

Solution: 💊

• Ability to add and remove items to the queue
• The Queue should be able to be run from start to finish
• Has tasks that can .start() and .stop() and has .onComplete() callback
• Tasks should have the ability to support timeout and retry
• The Queue should be able to paused/stopped, resumed/started, reset/canceled (⚠️️ resume is not supported, only cancel ⚠️️)
• Queues should be able to be nested? Queues within queues? (maybe) (reach-goal, ⚠️️ not currently supported ⚠️️) 🤔

Example:

let networkTasks: [NetworkTask] = (0..<5).map { _ in // Create 5 network tasks
   .init { (_ value: Any?) in
      guard let strValue: String = (value as? Data)?.stringUTF8 else { XCTFail(); return }
      Swift.print("strValue:  \(strValue) ✨")
   }
} // For loop network task
let queue: Queue = .init()
queue.onComplete = {
   Swift.print("queue test completed ✅")
   expectation.fulfill() // If this line is called, then test passed
}
queue.enqueue(networkTasks) // Add tasks and begin executing

Todo: 📝

• Look at pagination service project for mock-api inspo ✅
• Take a look at TestRunner (it has FIFO style architecture) ✅
• Add timeout callback? ✅ (would need to separate network and db transaction in one task, in order to cancel transaction if network task is not complete etc) (can use Dispatchueue with timeout ?)
• Do research on other cancelable closures in swift. ✅ There should be another one in your dispatch research etc (DispatchWorkItem)
• Do tests with timers and background calls etc ✅
• Test with run, add and cancel buttons 👈
• Explain some of the use cases
• Maybe subclass NSOperation (investigation needed) see issues ✨
• Add support for result type? instead of just Any?
• Add hasNext() like TestRunner? 🚫